A typical home theater system comprises a display unit, a DVD player or other signal source, an audio video control receiver (AVR), and multiple speakers. The speakers may comprise a center speaker, a subwoofer and two or more pairs (left and right) of surround speakers. The home theater system includes a home theater decoder that creates multiple digital audio signals, which are assigned to the speakers respectively. Each digital audio signal may be composed of a succession of 24-bit samples at a rate of 48 kSa/s. A complete multi-channel audio sample comprises one sample for each channel. Thus, in the case of an eight channel home theater audio system, one multi-channel sample comprises eight 24-bit samples.
The home theater decoder supplies the digital audio signals to the AVR, which converts the digital audio signals to analog form for driving the speakers over wired speaker connections between the AVR and the respective speakers. Alternatively, however, the AVR may include a radio transmitter that transmits the digital audio data wirelessly to radio receivers incorporated in the speakers. In this case, the AVR supplies the digital audio signals to a packetizer, which constructs a transmission packet having a payload that contains the digital audio data for several, e.g. 48, multi-channel audio samples. In the case of the eight channel system, the transmission packet may contain the data for six multi-channel samples.
The radio transmitter employs the transmission packet data bits to modulate a carrier at the frequency of a selected communication channel and transmits the modulated signal via an antenna. In each speaker, a radio receiver receives the modulated signal and detects the modulating transmission packet data bits. An audio processor included in the speaker recovers the digital audio signal assigned to that speaker from the successive transmission packets, converts the digital audio signal to analog form, amplifies the analog audio signal and supplies the audio signal to the audio driver.
It is possible for one or more packets to be lost or damaged in transmission from the AVR to a speaker. This leaves a gap in the sound information and degrades the quality of the reproduction of the audio signal. It is possible to reduce the degradation through various signal processing techniques such as interleaving packets and interpolating between lost or damaged data points.